Perhaps the most exciting, and most useful, area of electronics today involves the gathering and manipulation of multiple real-time data signals. A real-time signal is any signal whose transmission between two particular points cannot tolerate interruption.
A real-time system therefore, as a result of processing real-time data signals, has well-defined and fixed time constraints which require the completion of process tasks within the defined time constraints or they suffer system failure.
Examples of real-time systems included dedicated applications, such as, weather tracking and teleconferencing systems, control systems developed for manufacturing environments, computer systems designed to supervise scientific and medical experiments, and advanced television technology.
As an example, consider a video teleconferencing paradigm involving four remote sites. A user, seated at a desk peers into a computer, and sees, besides the user's own image, which ensures that the camera projecting that image is correctly positioned, the other three participants at their respective sites. All four data streams appear within an associated display window, and each of the windows is full motion, i.e., real-time.
Thus, besides the user's locally projected image, there are three additional real-time video sources simultaneously received from the other sites. Thus, all windows are simultaneously active.
Traditionally, a system implemented to meet the needs presented by this paradigm would utilize four individual video controllers, each overseeing the contents of one of the four display windows. Each video controller would be comprised of a processing unit coupled with an associated memory storage device. Thus, there would be a one-to-one correlation between video controllers and received video data streams.
Each of the video controllers would drive a stream of output data to a multiplexer which was coupled between the multiple video controllers and the display mechanism. The multiplexer would transition among the four video controllers creating the desired output display. A necessary requirement of this approach being that all of the received data sources being genlocked together. In essence, the multiplexer would select between the multiple received data sources by turning a first data stream "on," turning a first data stream "off," and turning a second data stream "on," turning a second data stream "off," and turning a third data stream "on," etc.
The failings inherent to the above approach are twofold. First, this approach provides a very fragmented solution to the management of multiple received data streams, and second, this approach, which utilizes a separate microprocessor and a separate storage buffer for each received data stream, is inordinately expensive, and thus undesirable for common use.
Accordingly, there exists a need in the art for a system and method for simultaneously processing multiple received signal sources utilizing a single memory storage device.
There exists a still further need in the art for a system and method for processing multiple received signal sources which may be implemented within a single easily replaceable integrated circuit.
There exists a still further need in the art for a system and method for processing multiple received signal sources which is cost effective and reliable.
There exists a still further need in the art for a system and method for processing multiple received signal sources whose implementation is presented as an integrated whole, built top-down to fit into a consistent, coherent conceptual frame work.